Coated sand by Dr. Ke Luoning Germany during World War II invention, the process is powdered phenolic thermosetting resin sand mechanically mixed with the original, when heat cured. After developing into a thermoplastic phenolic resin plus the latent curing agent (hexamine) and a lubricant coating process through certain production formulated as coated sand coated sand, coated sand is heated when the surface of the resin coated sand melt-coated sand, at 乌洛托 coated sand product decomposition of methylene effect, the molten resin is rapidly transformed into a non-linear structure by melt processing of coated sand body structure, so that the coated sand curing. High temperature coated sand: The sand coated sand generally refers to thermal intensity, long time resistant, high temperature deformation, rather than its high refractoriness. It is through a special process recipe technology (usually when a certain amount of inert materials such as silica sand coated sand milling, high chromium ore, carbonaceous material or other inert materials, etc.), to produce a superior high temperature performance and integrated casting The new coated sand properties. High temperature, high strength, low inflation, low gas, gas, etc. slow hair. Especially for complex thin-walled precision iron castings (such as automobile engine block, cylinder head, etc.) as well as the high demand of castings (such as container train horn and brakes buffer housing, etc.) production, which can effectively eliminate the sticky sand, deformation, thermal cracking and porosity and other casting defects present the main problems in China coated sand detection is (1) detection means most companies are not perfect. Basic stay in detecting temperature strength, melting point, particle size and volume of the primary stage of hair; (2) domestic coated sand testing equipment accuracy and stability is not high, the same kind of equipment of different manufacturers use in field conditions coated sand company, coated sand detected relatively large differences in performance sometimes, for example, room temperature tensile strength can be a difference of 10 kg or more, a difference of 5 ml or more gas evolution. Currently more advanced testing equipment including high temperature coated sand performance tester, send gas meter, hot strength tester, coated sand coated sand plant _ _ provided by Qingdao Qingdao Heng Heng Machinery Co. Qingdao Heng Machinery Co., Ltd. (www.thjidian.com) strong, credible, Shandong Qingdao Cleaning equipment industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Qingdao Heng and you hand into the brilliant, for a better future!